This invention relates to a two-cycle fuel injection engine and more particularly to an improved arrangement for driving an engine accessory and for lubricating the drive shaft of that accessory.
In many instances, certain auxiliaries or accessories for an internal combustion engine are driven by a drive shaft that is positioned externally of the engine. In this case, these externally positioned drive shafts are remotely positioned from the lubricating system of the engine and thus are not lubricated by the nornal lubricating system of the engine. This is particularly true with respect to two-cycle internal combustion engines wherein the engine itself may be lubricted through mixture of lubricant with its fuel or with its intake charge. When a remotely positioned accessory is driven by a remotely positioned drive shaft, that drive shaft will not be lubricated by the engine lubricating system.
It is, therefore, a principal object of this invention to provide an improved arrangement for driving an engine accessory and for lubricating a drive shaft of that accessory.
It is a further object of this invention to provide an accessory drive for an internal combustion engine wherein an externally positioned shaft is provided with its own lubricating system.
One form of accessory which is normally externally positioned from an engine and driven from an external drive shaft is a fuel injection pump. With both diesel and gasolne fuel injected engines, the fuel injection pump is normally positioned externally of the engine and is driven by an external drive shaft. As such, the drive shaft cannot be lubricated conveniently from the engine lubricating system.
It is, therefore, a still further object of this invention to provide an improved driving and lubricating arrangement for the fuel injection pump of an internal combustion engine.
In some instances, it has been proposed to employ a pair of intermeshing gears as an arrangement for pumping lubricant for lubricating as associated shaft. Although such arrangements have advantages, the previously proposed arrangements have employed bevel gears for this purpose. However, a bevel gear drive does not provide as adequate a source of lubrication under pressure as other types of gears.
It is, therefore, a further object of this invention to provide an improved arrangement for employing intermeshing gears as a source for pumping lubricant as well as for establishing a driving relationship between a pair of shafts.
In many instances, a given shaft is called upon to drive a plurality of accessories at different speed ratios. For example, in an internal combustion engine of the two-cycle type as aforedescribed, the same shaft may be employed for driving both a fuel injection pump and a lubricant pump. However, the driving ratios between the shaft and the two pumps can be considerably different. Of course it is desirable to lubricate the gears and the shafts and it is, therefore, a further object of this invention to provide an improved arrangement for driving a plurality of accessories and lubricating the driving shaft for the accessories.